Description
Part 1: What is Doppler Radar and how does it work?
Go to https://www.weather.gov/jetstream/doppler_introClick on how radar works in the upper right corner
- What exactly is Doppler shift?How does the Doppler effect work on a train whistle as it rolls towards and then away from you?How does dual polarization help with identifying tornadoes?
- Click in the upper right corner: Reflectivity.How does base reflectivity differ from composite?Be sure to compare the two sample images centered along the Okla. and Texas line
- Read carefully, the section on velocity by clicking velocity in the upper right corner.Scan the graphic depicting the wind-field southeast of Lake Michigan (Indianapolis radar).What is the direction of the wind-field?
- Why is storm relative motion important?
- Click on precipitation in the upper right corner. What two types of images of precipitation are portrayed using Doppler Radar?
Part 2: Birmingham, AL Doppler Radar:
Go to Understanding Radar – Weather Underground
Composite Reflectivity 124 NMI range SEE FIRST PICTURE in attachment
6. Weather Undergrounds Composite Reflectivity (echo intensity) figure merges the highest reflectivity from all scans. From this image, how would you explain the structure and intensity of this storm?(Use directions relative to Montgomery AL and Columbus GA)
Storm Total Surface Rainfall Accumulation 124 NMI Range
SEE SECOND PICTURE in attachment
7. Refer to Understanding Radar (Weather Underground). How could this type of image be useful for cities like Birmingham or Columbus?How would the impacts of a 3 to 5 inch rainfall event differ in Columbus and Montgomery versus a rural area?
Echo Tops 124 NMI Range SEE THIRD PICTURE in attachment
8. What type of clouds are present here based on the maximum echo value?
Velocity Azimuth Display Wind Profile 124 NMI Range
SEE FOURTH PICTURE in attachment
9. Examine the 23:43 column for Birmingham AL.When the plane takes off, what in the wind direction and velocity?At what altitude(s) does the wind shift?Describe this shift in direction and velocity.
How would you describe the trend of this profile over time at 12,000 feet (youngest to the left, oldest to the right)? Incorporate direction, speed, and altitude into your answer (note KFT = altitude in thousands of feet).
NOAA: 250 MB Chart SEE FIFTH PICTURE in attachment
10. Examine the 250 mb chart (approx. 36,000 ft) above taken at 8 am CDT 10/4/21. What are the wind speeds and direction of winds over Birmingham, AL? Do they coincide with the Velocity Azimuth Display Wind Profile figure? {Compare the 250 mb Chart to the 23:37 (6:37 pm) data from the Velocity Azimuth Display Wind Profile}
NEXRAD Part 3:Bethel AK 10/4/21 at 3:26 pm ADT
SEE SIXTH PICTURE in attachment
11. Using your FAA Guide to ppt. intensity handout, Describe the precipitation intensity that is occurring in Southwestern Alaska using Bethel as a base point.
SEE SIVENTH PICTURE in attachment
12. After checking the rain/snow icon, describe the two types of precipitation occurring.Use the FAA Guide To describe intensity.Which mode of ppt is the most dangerous for flying and where is it occurring?
SEE EIGHTH PICTURE in attachment
13. Based on the data above (including the two previous images), what type of cloud dominates this storm? Justify your answer.
SEE NINETH PICTURE in attachment
14. How many inches of snow have fallen at Bethels airport? (Use a ratio of 10 of snow = 1 of rainfall)?
SEE TENTH PICTURE in attachment
15. Assume that you are taking off at 23:32 in a Boeing 737 (Bethels airport handles commercial jets), describe the wind velocity and direction at take-off and at what altitudes does it change? Notice that from 9 KFT to 30 KFT the direction remains constant.What is this direction?What is the velocity at 18 KFT (approx. 500 mb) and 30 KFT (approx. 300 mb)?
Part 4: How do I Access radar images at weather underground?
- https://www.wunderground.com/
- Click the maps and radar heading
- Scroll to radar maps and click
- Map of USA appears. Find an area with weather
- Click US regions and scroll to an appropriate region and click [WA-Tacoma (ATX) for example]
- Regional image appears and select a doppler radar [Portland OR (RTX)]
- Base reflectivity scan at .5° 248 NMappears
- Scroll on icon Base reflectivity scan at .5° 248 NM appears for additional images
16. Find a region of the USA that is having some weather.Describe what you are seeing based on a 124 NM Composite scan (attach the image).